Many packaging bags and many closing devices for this purpose have already been proposed.
The majority of closing devices known for this purpose comprises two complementary profiles, for example of male/female type or of velvet/hook type, or again of complementary hook type, carried by respective support webs.
The appended FIG. 5 shows the mouth of a reclosable bag known from document FR 2 628 067.
FIG. 5 shows the two main walls 10, 20 of the bag at the mouth of the latter. The appended FIG. 5 also shows a closing device 100 comprising two complementary closing profiles 110, 120 carried by respective support webs 112, 122 fixed respectively on the walls 10 and 20.
More precisely, the fastening zones of the support webs 112, 122 on the walls 10 and 20 are referenced 114 and 124.
It is evident from FIG. 5 that the fastening zone 114 of the support web 112 on the wall 10 is not superposed on the male profile 110 but offset relative to the latter. Alternatively, the fastening zone 124 of the support web 122 on the wall 20 could be offset relative to the female profile 120. In this way, the web 112 forming a support to the male profile 110 is articulated on the wall 10 at the fastening zone 114. As is described in document FR 2 628 067, the foregoing arrangement avoids internal pressure to the bag from being applied to the closing profiles 110, 120 and tends to separate the latter. In fact, by way of the arrangement described above and as shown in FIG. 5, the separation of the walls 10, 20 of the bag (to open the latter) results in possible pivoting of the support web 110 at the hinge zone formed by its fastening, without risk of separation of the closing profiles 110, 120.
Bags responding to the arrangement shown in FIG. 5 have already provided major service and make reopening of the bag difficult, so as to ensure its user that its contents cannot be taken out easily.
Document FR 2 963 927 also proposes that the two zones 114, 124 are located at a distance from and on either side of the corresponding complementary profiles 110, 120 in such a way that one of the articulated webs 112 is directed towards the interior of the bag, whereas the other articulated web 122 is directed towards its mouth.
These bags also resist internal and external stresses of the walls of the bag, to such a point where today it proves very difficult to open it without damaging the closing device 100 or the walls of the bag.
But in some cases, it can prove necessary to be able to open the bag without damaging it to access its contents and be sure of reclosing it after opening.
Such a bag for example applies to the field of packaging harmful products, such as dishwasher tablets. In fact, it is important to be able to ensure users that the bag stays closed between two uses, especially to prevent children accessing its contents, and letting parents open and reclose the bag several times without risking damaging it, and preferably without successive openings and closings being too difficult.
U.S. Pat. No. 4,878,763 describes a structure of a reclosable bag comprising walls on which are fixed slide closing strips and configured to resist opening during application of a force to the mouth.
Document WO 02/074645 describes a reclosable bag comprising a gusset and a closing device. During opening of the bag, access to the contents of the bag is granted between the gusset and a wall opposite the bag.